Build Redis From Scratch

This repository contains an implementation of a simplified Redis-like in-memory database built using Go. The project follows a step-by-step guide and covers building a server, RESP parsing, implementing commands, and adding data persistence.

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Features

1. Custom Server:

   • Implements a custom TCP server to handle Redis-like client connections and requests.

2. RESP Parsing:

   • Built both a RESP reader and writer to handle Redis Serialization Protocol for processing client commands and sending responses.

3. Command Execution:

   • Supports core Redis commands for strings (SET, GET) and hashes (HSET, HGET).

4. Concurrency:

   • Utilized Go routines to handle multiple simultaneous client connections.

5. Data Persistence:

   • Developed an Append Only File (AOF) mechanism to log executed commands and restore the state upon server restart.

6. Scalable Design:

   • Modular code structure with individual files for server logic, RESP parsing, and AOF handling.

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Installation

Prerequisites

• Go (version 1.18 or later)
• Redis CLI (redis-cli)

Setup

1. Clone the repository:

   git clone https://github.com/yourusername/build-redis-from-scratch.git
   cd build-redis-from-scratch

2. Run the server:

   go run main.go

3. Interact with the server using redis-cli:

   redis-cli -h 127.0.0.1 -p 6379

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Implemented Commands

• String Commands:

  • SET key value: Store a key-value pair.
  • GET key: Retrieve the value associated with a key.

• Hash Commands:

  • HSET key field value: Set a field in a hash.
  • HGET key field: Get the value of a field in a hash.

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Project Structure

.
├── aof.go         # Handles data persistence with Append Only File (AOF)
├── handler.go     # Contains logic to process client commands
├── main.go        # Entry point for the Redis server
├── resp.go        # Implements RESP parsing (reader and writer)
└── README.md      # Documentation

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How It Works

1. RESP Parsing

• The server uses a custom RESP reader (resp.go) to decode incoming commands and a writer to encode responses.

2. Concurrency

• Uses Go routines to manage multiple client connections efficiently.

3. Data Persistence

• Implements AOF to store all executed commands for recovery during a server restart.

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Usage Examples

Setting and Getting a Key

redis-cli -h 127.0.0.1 -p 6379
127.0.0.1:6379> SET name "RedisClone"
OK
127.0.0.1:6379> GET name
"RedisClone"

Using Hashes

redis-cli -h 127.0.0.1 -p 6379
127.0.0.1:6379> HSET user name "Alice"
1
127.0.0.1:6379> HGET user name
"Alice"

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Planned Features

• Add support for additional Redis data types (e.g., lists, sets, sorted sets).
• Improve concurrency with better locking mechanisms.
• Extend RESP parsing for pipelined commands.

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License

This project is licensed under the MIT License.